A multi-method approach to study the geodynamic evolution of eastern Dronning Maud Land in East Antarctica by integrating geophysical data with surface geology

Planet Earth has not always been as it appears today. Since billions of years, continents have been drifting continually caused by lateral variations of mantle density resulting in convection. Analyzing the movement of lithospheric plates back in eartha s history is essential for the determination o...

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Bibliographic Details
Main Author: Ruppel, Antonia
Other Authors: Lisker, Frank, Crispini, Laura
Format: Doctoral or Postdoctoral Thesis
Language:English
Published: Universität Bremen 2019
Subjects:
550
Online Access:https://media.suub.uni-bremen.de/handle/elib/1656
https://nbn-resolving.org/urn:nbn:de:gbv:46-00107622-19
Description
Summary:Planet Earth has not always been as it appears today. Since billions of years, continents have been drifting continually caused by lateral variations of mantle density resulting in convection. Analyzing the movement of lithospheric plates back in eartha s history is essential for the determination of the shape of ancient supercontinents. It further provides paleogeographic information and is vital for biogeographic and climate studies. Whereas the break-up of the former extensive landmass of Gondwana can be reconstructed fairly well by analyzing seafloor-spreading anomalies of the oceanic crust, the amalgamation of Gondwana still needs to be understood in more detail. This is because oceanic crust, that rarely exceeds 180 million years in age, does not provide any direct evidence for the amalgamation of Gondwana in Late Neoproterozoic/Early Palaeozoic times as well as for older supercontinent cycles. East Antarctica, once centerpiece of Gondwana, can be considered a rather stable region as it has not been affected by orogenic processes since the Early Paleozoic except for its Palaeo-Pacific margin. Furthermore, the Antarctic plate is mainly surrounded by mid-ocean ridges and features continental rift systems widely related to the break-up of Gondwana. Therefore, exposed regions that can be found in Sor Rondane, East Antarctica, are well suited for studying the formation and break-up of Gondwana as well as preceding collision and break-up processes. Sor Rondane is situated in eastern Dronning Maud Land and exposes the contact zone of crustal blocks of different origin and architecture. Therefore, it is considered to be a site of at least one suture between East and West Gondwana. This study examines the final amalgamation and break-up history of Gondwana by investigating Sor Rondane and adjacent regions. To answer those questions, a detailed understanding of the crustal architecture is essential. This encompasses the number of involved crustal fragments, the location of their boundaries and their geological ...